Closing the Window on Warm Dark Matter
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Adrien Christian René THOB
THE RELATIONSHIP BETWEEN THE MORPHOLOGY AND KINEMATICS OF GALAXIES AND ITS DEPENDENCE ON DARK MATTER HALO STRUCTURE IN SIMULATED GALAXIES Adrien Christian René THOB A thesis submitted in partial fulfilment of the requirements of Liverpool John Moores University for the degree of Doctor of Philosophy. 26 April 2019 To my grand-parents, René Roumeaux, Christian Thob, Yvette Roumeaux (née Bajaud) and Anne-Marie Thob (née Léglise). ii Abstract Galaxies are among nature’s most majestic and diverse structures. They can play host to as few as several thousands of stars, or as many as hundreds of billions. They exhibit a broad range of shapes, sizes, colours, and they can inhabit vastly differing cosmic environments. The physics of galaxy formation is highly non-linear and in- volves a variety of physical mechanisms, precluding the development of entirely an- alytic descriptions, thus requiring that theoretical ideas concerning the origin of this diversity are tested via the confrontation of numerical models (or “simulations”) with observational measurements. The EAGLE project (which stands for Evolution and Assembly of GaLaxies and their Environments) is a state-of-the-art suite of such cos- mological hydrodynamical simulations of the Universe. EAGLE is unique in that the ill-understood efficiencies of feedback mechanisms implemented in the model were calibrated to ensure that the observed stellar masses and sizes of present-day galaxies were reproduced. We investigate the connection between the morphology and internal 9:5 kinematics of the stellar component of central galaxies with mass M? > 10 M in the EAGLE simulations. We compare several kinematic diagnostics commonly used to describe simulated galaxies, and find good consistency between them. -
Letter of Interest Cosmic Probes of Ultra-Light Axion Dark Matter
Snowmass2021 - Letter of Interest Cosmic probes of ultra-light axion dark matter Thematic Areas: (check all that apply /) (CF1) Dark Matter: Particle Like (CF2) Dark Matter: Wavelike (CF3) Dark Matter: Cosmic Probes (CF4) Dark Energy and Cosmic Acceleration: The Modern Universe (CF5) Dark Energy and Cosmic Acceleration: Cosmic Dawn and Before (CF6) Dark Energy and Cosmic Acceleration: Complementarity of Probes and New Facilities (CF7) Cosmic Probes of Fundamental Physics (TF09) Astro-particle physics and cosmology Contact Information: Name (Institution) [email]: Keir K. Rogers (Oskar Klein Centre for Cosmoparticle Physics, Stockholm University; Dunlap Institute, University of Toronto) [ [email protected]] Authors: Simeon Bird (UC Riverside), Simon Birrer (Stanford University), Djuna Croon (TRIUMF), Alex Drlica-Wagner (Fermilab, University of Chicago), Jeff A. Dror (UC Berkeley, Lawrence Berkeley National Laboratory), Daniel Grin (Haverford College), David J. E. Marsh (Georg-August University Goettingen), Philip Mocz (Princeton), Ethan Nadler (Stanford), Chanda Prescod-Weinstein (University of New Hamp- shire), Keir K. Rogers (Oskar Klein Centre for Cosmoparticle Physics, Stockholm University; Dunlap Insti- tute, University of Toronto), Katelin Schutz (MIT), Neelima Sehgal (Stony Brook University), Yu-Dai Tsai (Fermilab), Tien-Tien Yu (University of Oregon), Yimin Zhong (University of Chicago). Abstract: Ultra-light axions are a compelling dark matter candidate, motivated by the string axiverse, the strong CP problem in QCD, and possible tensions in the CDM model. They are hard to probe experimentally, and so cosmological/astrophysical observations are very sensitive to the distinctive gravitational phenomena of ULA dark matter. There is the prospect of probing fifteen orders of magnitude in mass, often down to sub-percent contributions to the DM in the next ten to twenty years. -
Dark Energy and Dark Matter
Dark Energy and Dark Matter Jeevan Regmi Department of Physics, Prithvi Narayan Campus, Pokhara [email protected] Abstract: The new discoveries and evidences in the field of astrophysics have explored new area of discussion each day. It provides an inspiration for the search of new laws and symmetries in nature. One of the interesting issues of the decade is the accelerating universe. Though much is known about universe, still a lot of mysteries are present about it. The new concepts of dark energy and dark matter are being explained to answer the mysterious facts. However it unfolds the rays of hope for solving the various properties and dimensions of space. Keywords: dark energy, dark matter, accelerating universe, space-time curvature, cosmological constant, gravitational lensing. 1. INTRODUCTION observations. Precision measurements of the cosmic It was Albert Einstein first to realize that empty microwave background (CMB) have shown that the space is not 'nothing'. Space has amazing properties. total energy density of the universe is very near the Many of which are just beginning to be understood. critical density needed to make the universe flat The first property that Einstein discovered is that it is (i.e. the curvature of space-time, defined in General possible for more space to come into existence. And Relativity, goes to zero on large scales). Since energy his cosmological constant makes a prediction that is equivalent to mass (Special Relativity: E = mc2), empty space can possess its own energy. Theorists this is usually expressed in terms of a critical mass still don't have correct explanation for this but they density needed to make the universe flat. -
X-Ray Line Signal from Decaying Axino Warm Dark Matter
Physics Letters B 735 (2014) 92–94 Contents lists available at ScienceDirect Physics Letters B www.elsevier.com/locate/physletb X-ray line signal from decaying axino warm dark matter ∗ Ki-Young Choi a, , Osamu Seto b a Korea Astronomy and Space Science Institute, Daejon 305-348, Republic of Korea b Department of Life Science and Technology, Hokkai-Gakuen University, Sapporo 062-8605, Japan a r t i c l e i n f o a b s t r a c t Article history: We consider axino warm dark matter in a supersymmetric axion model with R-parity violation. In this Received 11 March 2014 scenario, axino with the mass ma˜ 7keVcan decay into photon and neutrino resulting in the X-ray line Received in revised form 14 May 2014 signal at 3.5 keV, which might be the origin of unidentified X-ray emissions from galaxy clusters and Accepted 3 June 2014 Andromeda galaxy detected by the XMM-Newton X-ray observatory. Available online 6 June 2014 © 2014 The Authors. Published by Elsevier B.V. This is an open access article under the CC BY license Editor: A. Ringwald 3 (http://creativecommons.org/licenses/by/3.0/). Funded by SCOAP . 1. Introduction In Section 2 we introduce the model of axino dark matter and in Section 3 we consider the R-parity violation and decay of axinos. Various astrophysical and cosmological observations provide We summarize in Section 4. convincing evidences for the existence of dark matter (DM). Dark matter distribution spans in wide range of scales from galaxy to 2. -
Cosmology Meets Condensed Matter
Cosmology Meets Condensed Matter Mark N. Brook Thesis submitted to the University of Nottingham for the degree of Doctor of Philosophy. July 2010 The Feynman Problem-Solving Algorithm: 1. Write down the problem 2. Think very hard 3. Write down the answer – R. P. Feynman att. to M. Gell-Mann Supervisor: Prof. Peter Coles Examiners: Prof. Ed Copeland Prof. Ray Rivers Abstract This thesis is concerned with the interface of cosmology and condensed matter. Although at either end of the scale spectrum, the two disciplines have more in common than one might think. Condensed matter theorists and high-energy field theorists study, usually independently, phenomena embedded in the structure of a quantum field theory. It would appear at first glance that these phenomena are disjoint, and this has often led to the two fields developing their own procedures and strategies, and adopting their own nomenclature. We will look at some concepts that have helped bridge the gap between the two sub- jects, enabling progress in both, before incorporating condensed matter techniques to our own cosmological model. By considering ideas from cosmological high-energy field theory, we then critically examine other models of astrophysical condensed mat- ter phenomena. In Chapter 1, we introduce the current cosmological paradigm, and present a somewhat historical overview of the interplay between cosmology and condensed matter. Many concepts are introduced here that later chapters will follow up on, and we give some examples in which condensed matter physics has had a very real effect on informing cosmology. We also reflect on the most recent incarnations of the condensed matter / cosmology interplay, and the future of these developments. -
Sterile Neutrinos As Dark Matter
Sterile neutrinos as dark matter Alexey Boyarsky October 23, 2018 1 / 36 Neutrino dark matter Neutrino seems to be a perfect dark matter candidate: neutral, long-lived, massive, abundantly produced in the early Universe Cosmic neutrinos I We know how neutrinos interact and we can compute their 3 primordial number density nν = 112 cm− (per flavour) I To give correct dark matter abundance the sum of neutrino masses, P m , should be P m 11 eV ν ν ∼ Tremaine-Gunn bound (1979) I Such light neutrinos cannot form small galaxies { one would have to put too many of them and violated Pauli exclusion principle I Minimal mass for fermion dark matter 300 400 eV ∼ − I If particles with such mass were weakly interacting (like neutrino) { they would overclose the Universe 2 / 36 "Between friends" I The final blow to neutrino as dark matter came in mid-80s when M. Davis, G. Efstathiou, C. Frenk, S. White, et al. \Clustering in a neutrino-dominated universe" I They argued that structure formation in the neutrino dominated Universe (with masses around 100 eV would be incompatible with the observations) http://www.adsabs.harvard.edu/abs/1983ApJ...274L...1W Abstract The nonlinear growth of structure in a universe dominated by massive neutrinos using initial conditions derived from detailed linear calculations of earlier evolution has been simulated The conventional neutrino-dominated picture appears to be ruled out. 3 / 36 Two generalizations of neutrino DM I Dark matter cannot be both light and weakly interacting at the same time I To satisfy Tremaine-Gunn -
Cosmological N-Body Simulations with Generic Hot Dark Matter
Prepared for submission to JCAP Cosmological N-body simulations with generic hot dark matter Jacob Brandbyge,a;b Steen Hannestada aDepartment of Physics and Astronomy, University of Aarhus, Ny Munkegade 120, DK{8000 Aarhus C, Denmark bCentre for Star and Planet Formation, Niels Bohr Institute & Natural History Museum of Denmark, University of Copenhagen, Øster Voldgade 5-7, DK{1350 Copenhagen, Denmark E-mail: [email protected], [email protected] Abstract. We have calculated the non-linear effects of generic fermionic and bosonic hot dark matter components in cosmological N-body simulations. For sub-eV masses, the non- linear power spectrum suppression caused by thermal free-streaming resembles the one seen for massive neutrinos, whereas for masses larger than 1eV, the non-linear relative suppression of power is smaller than in linear theory. We furthermore find that in the non-linear regime, one can map fermionic to bosonic models by performing a simple transformation. arXiv:1706.00025v1 [astro-ph.CO] 31 May 2017 Contents 1 Introduction1 2 Hot dark matter in linear theory2 2.1 Power spectrum suppression2 2.2 Phase space distribution of the hot dark matter4 2.3 Current constraints from linear theory4 3 Simulation methods6 3.1 Cosmology and initial conditions6 3.2 Different hot dark matter simulation methods7 3.3 The correlation of bulk and thermal velocities7 4 Non-linear results8 4.1 Generic hot dark matter power spectrum suppression 10 4.2 Fermions versus bosons 11 4.3 Convergence 13 5 Discussion and conclusions 13 1 Introduction Although many different types of observations constrain the dominant dark matter compo- nent of the Universe to be cold, a sub-dominant hot dark matter (HDM) component cannot be excluded. -
Dark Matter and Dark Energy: Summary and Future Directions
Dark Matter and Dark Energy: Summary and Future Directions By John Ellis TH Division, CERN, Geneva, Switzerland CERN–TH/2003-086 astro-ph/0304183 April 2003 This paper reviews the progress reported at this Royal Society Discussion Meeting and advertizes some possible future directions in our drive to understand dark matter and dark energy. Additionally, a first attempt is made to place in context the exciting new results from the WMAP satellite, which were published shortly after this Meeting. In the first part of this review, pieces of observational evidence shown here that bear on the amounts of dark matter and dark energy are reviewed. Subsequently, particle candidates for dark matter are mentioned, and detection strategies are discussed. Finally, ideas are presented for calculating the amounts of dark matter and dark energy, and possibly relating them to laboratory data. Keywords: cosmology, particle physics, dark matter, dark energy 1. The Density Budget of the Universe It is convenient to express the mean densities ρi of various quantities in the Universe in terms of their fractions relative to the critical density: Ωi ρi/ρcrit. The theory of cosmological inflation strongly suggests that the the total≡ density should be very close to the critical one: Ωtot 1, and this is supported by the available data on the cosmic microwave background' radiation (CMB) (Bond 2003). The fluctuations 5 observed in the CMB at a level 10− in amplitude exhibit a peak at a partial wave ` 200, as would be produced∼ by acoustic oscillations in a flat Universe with ∼ Ωtot 1. At lower partial waves, ` 200, the CMB fluctuations are believed to be dominated' by the Sachs-Wolfe effect due to the gravitational potential, and more acoustic oscillations are expected at larger `>200, whose relative heights depend on the baryon density Ωb. -
Warm Dark Matter
Cosmology in the Nonlinear Domain: Warm Dark Matter Katarina Markoviˇc M¨unchen 2012 Cosmology in the Nonlinear Domain: Warm Dark Matter Katarina Markoviˇc Dissertation an der Fakult¨atf¨urPhysik der Ludwig{Maximilians{Universit¨at M¨unchen vorgelegt von Katarina Markoviˇc aus Ljubljana, Slowenien M¨unchen, den 17.12.2012 Erstgutachter: Prof. Dr. Jochen Weller Zweitgutachter: Prof. Dr. Andreas Burkert Tag der m¨undlichen Pr¨ufung:01.02.2013 Abstract The introduction of a so-called dark sector in cosmology resolved many inconsistencies be- tween cosmological theory and observation, but it also triggered many new questions. Dark Matter (DM) explained gravitational effects beyond what is accounted for by observed lumi- nous matter and Dark Energy (DE) accounted for the observed accelerated expansion of the universe. The most sought after discoveries in the field would give insight into the nature of these dark components. Dark Matter is considered to be the better established of the two, but the understanding of its nature may still lay far in the future. This thesis is concerned with explaining and eliminating the discrepancies between the current theoretical model, the standard model of cosmology, containing the cosmological constant (Λ) as the driver of accelerated expansion and Cold Dark Matter (CDM) as main source of gravitational effects, and available observational evidence pertaining to the dark sector. In particular, we focus on the small, galaxy-sized scales and below, where N-body simulations of cosmological structure in the ΛCDM universe predict much more structure and therefore much more power in the matter power spectrum than what is found by a range of different observations. -
Supersymmetric Dark Matter Candidates in Light of Constraints from Collider and Astroparticle Observables Jonathan Da Silva
Supersymmetric Dark Matter candidates in light of constraints from collider and astroparticle observables Jonathan da Silva To cite this version: Jonathan da Silva. Supersymmetric Dark Matter candidates in light of constraints from collider and astroparticle observables. High Energy Physics - Phenomenology [hep-ph]. Université de Grenoble, 2013. English. NNT : 2013GRENY033. tel-00912650v2 HAL Id: tel-00912650 https://tel.archives-ouvertes.fr/tel-00912650v2 Submitted on 19 Jan 2017 HAL is a multi-disciplinary open access L’archive ouverte pluridisciplinaire HAL, est archive for the deposit and dissemination of sci- destinée au dépôt et à la diffusion de documents entific research documents, whether they are pub- scientifiques de niveau recherche, publiés ou non, lished or not. The documents may come from émanant des établissements d’enseignement et de teaching and research institutions in France or recherche français ou étrangers, des laboratoires abroad, or from public or private research centers. publics ou privés. THESE` Pour obtenir le grade de DOCTEUR DE L’UNIVERSITE´ DE GRENOBLE Specialit´ e´ : Physique Theorique´ Arretˆ e´ ministeriel´ : 7 aoutˆ 2006 Present´ ee´ par Jonathan DA SILVA These` dirigee´ par Genevieve` BELANGER´ prepar´ ee´ au sein du Laboratoire d’Annecy-le-Vieux de Physique Theorique´ (LAPTh) et de l’Ecole´ Doctorale de Physique de Grenoble Supersymmetric Dark Matter candidates in light of constraints from collider and astroparticle observables These` soutenue publiquement le 3 juillet 2013, devant le jury compose´ de : Dr. Rohini GODBOLE Professeur, CHEP Bangalore, Inde, Presidente´ Dr. Farvah Nazila MAHMOUDI Maˆıtre de Conferences,´ LPC Clermont, Rapporteur Dr. Ulrich ELLWANGER Professeur, LPT Orsay, Rapporteur Dr. Celine´ BŒHM Charge´ de recherche, Durham University, Royaume-Uni, Examinatrice Dr. -
The Mond Phenomenology
THE MOND PHENOMENOLOGY B. FAMAEY1 & S. McGAUGH2 1Observatoire Astronomique, Universit´ede Strasbourg, CNRS, UMR 7550, France 2Department of Astronomy, Case Western Reserve University, Cleveland, USA The ΛCDM cosmological model is succesful at reproducing various independent sets of obser- vations concerning the large-scale Universe. This model is however currently, and actually in principle, unable to predict the gravitational field of a galaxy from it observed baryons alone. Indeed the gravitational field should depend on the relative contribution of the particle dark matter distribution to the baryonic one, itself depending on the individual assembly history and environment of the galaxy, including a lot of complex feedback mechanisms. However, for the last thirty years, Milgrom's formula, at the heart of the MOND paradigm, has been consistently succesful at predicting rotation curves from baryons alone, and has been resilient to all sorts of observational tests on galaxy scales. We show that the few individual galaxy rotation curves that have been claimed to be highly problematic for the predictions of Mil- grom's formula, such as Holmberg II or NGC 3109, are actually false alarms. We argue that the fact that it is actually possible to predict the gravitational field of galaxies from baryons alone presents a challenge to the current ΛCDM model, and may indicate a breakdown of our understanding of gravitation and dynamics, and/or that the actual lagrangian of the dark sector is very different and richer than currently assumed. On the other hand, it is obvious that any alternative must also in fine reproduce the successes of the ΛCDM model on large scales, where this model is so well-tested that it presents by itself a challenge to any such alternative. -
Gamma-Ray Line Emission from OB Associations and Young Open Knödlseder, J
Title Authors Reference ---2002--- Gamma-ray line emission from OB associations and young open KnÖdlseder, J. et al. A&A 390, 945-960 (2002) clusters. II. The Cygnus region Detectability and characteristics of the 2.223 MeV line emission from Guessoum, N, & Jean, P. A&A, 396, 157-169 (2002) nearby X-ray binaries New Astronomy Reviews, Volume 46, Gamma-ray lines in advection dominated accretion flows Prantzos, N. Issue 8-10, p. 567-571 (2002) New Astronomy Reviews, Volume 46, SPI cosmic radioactivity measurements in perspective Schoenfelder, V. Issue 8-10, p. 597-604 (2002) Pre-launch calibration campaign of the gamma-ray spectrometer aboard New Astronomy Reviews, Volume 46, Schanne, S. the INTEGRAL satellite Issue 8-10, p. 605-609 (2002) New Astronomy Reviews, Volume 46, Instrumental lines of astrophysical relevance in TGRS and SPI Weidenspointner, G. et al. Issue 8-10, p. 625-629 (2002) Proceedings of the XXII Moriond Coded-Mask Imaging in Gamma-Ray Astronomy - Separating the Real Astrophysics Meeting The Gamma- Skinner, G.K. and Imaginary parts of a Complex subject Ray Universe (Les Arcs, March 9-16, 2002) Proceedings of the XXII Moriond Astrophysics Meeting The Gamma Observation of Gamma-ray Bursts with INTEGRAL Gotz, D. & Mereghetti, S. Ray Universe (Les Arcs, March 9-16, 2002) Proceedings of the XXII Moriond Astrophysics Meeting The Gamma- The INTEGRAL Science Data Centre Beckmann, V. Ray Universe (Les Arcs, March 9-16, 2002) Proceedings of the XXII Moriond Astrophysics Meeting The Gamma- The INTEGRAL Mission Hermsen, W. & Winkler, C. Ray Universe (Les Arcs, March 9-16, 2002) Proceedings of the XXII Moriond Astrophysics Meeting The Gamma- IBIS/PICsIT Data and Analysis Stephen, J.B.